In what appears to be a preview of the general election, should Joe Biden win the Democratic nomination, the former Vice President was the target of President Trump’s many jabs last night at a campaign rally in Pennsylvania. All the rust belt states will be fighting ground in 2020, but perhaps none more so than the Keystone State. After all, if Trump could once again peel this reliably blue state away from Democrats, the chances of his winning re-election go up exponentially.

Likewise, if Democrats hold Pennsylvania in 2020, their chances of upsetting Trump and taking back the White House improve dramatically. Unlike most prior years, where Republicans wouldn’t bother to compete in the state since it was a foregone conclusion, 2020 could be a banner presidential year for Pennsylvania to take center stage.

Speaking at a rally in Montoursville, Pa., the President argued that Joe Biden abandoned Pennsylvania when he went into politics by deciding to set up his career in Delaware, as the Washington Post reports:

“Biden deserted you,” he told the crowd at a campaign rally in Montoursville, Pa., located about 80 miles west of Scranton. “I guess he was born here, but he left you, folks. He left you for another state.”

The eyebrow-raising assertion received only a muted response from the audience, suggesting that even Trump’s die-hard supporters weren’t necessarily sold on the claim. Over the years, Biden has repeatedly referenced his Scranton roots, which pundits see as a strategic political move geared to appeal to working-class voters in a crucial swing state. But locals have consistently insisted that his affection for the hardscrabble city is genuine.

“You think it’s an opportunist thing, but it’s not,” his childhood friend, Tom Bell, told the Scranton Times-Tribune in 2008. “The guy’s that way. He’s always been. Before he was even in the limelight.”

Trump is framing the presidential race as a test of loyalties by asking voters to decide which candidate has best represented Pennsylvania over the years. His continued line of attack down this road will likely hinge on pointing to liberal policies which allegedly hurt the coal industry in this mining state, and try to hang that around Biden’s neck as originating from the Democratic Party and various environmental policies.

Trump only won Pennsylvania by a mere 50,000 votes in 2016 in a state where over six million votes were cast. The margin is razor thin, which means his cushion for error is very low and Biden, unlike Hillary Clinton, who couldn’t connect with rust belt voters, will naturally have an advantage.

Most Important State in 2020?, a local news outlet goes a step further and says that Pennsylvania will literally be the most important state in 2020:

Pennsylvania is arguably the most important of all, for reasons including the fact whoever wins Pennsylvania is likely to become president.

Or looked at another way, if a candidate lacks what it takes to sway Pennsylvanians, they likely lack what it takes to win the election.

“The fact is, precious few states are likely to matter, and Pennsylvania has emerged as one of the top-tier states,” says political analyst G. Terry Madonna of Franklin & Marshall College. “We’re going to be, in effect, ground zero.”

Being at ground zero, in today’s ultra-intense, ultra-polarized, all-encompassing political world, means Pennsylvanians are in for a memorable, even historic, experience.

Pennsylvania’s importance is obvious for plenty of reasons.

The candidates are already focusing on it. Democratic front runner Joe Biden put his national headquarters in Philadelphia and appeared here right after announcing his candidacy.

A recent Los Angeles Times story began, “President Trump and Joe Biden have twin obsessions: with each other and with the state of Pennsylvania.”

If Donald Trump started with every state he won in 2016, but lost Pennsylvania, he’d still win the Electoral College and a second term. Trump could even lose Pennsylvania and Wisconsin and still win a second term. If he were to lose Pennsylvania, Wisconsin, and give back Michigan, that would be enough to topple his 2016 coalition and put a Democrat back in the White House.

Out of the blue-leaning rust belt states that Trump won in 2016, Pennsylvania has the most delegates at 20, followed by 16 for Michigan, and 10 for Wisconsin. He could lose a combination of these states and still retain the needed 270 electoral voters with the electoral math cut in various ways.

Trump’s strategy to establish a beachhead in the hardest-to-win state, and keep pushing forward to tear down Biden’s rust belt credentials is where his campaign has chosen to start.

So far, Biden has had the advantage of leading in most polls among Democratic primary voters (except Iowa?) and has been able to ignore other contenders and focus solely on Donald Trump. That dynamic will shift in the coming weeks as the first Democratic debate comes into focus in June and other voices on Biden’s side are given opportunities to tear into the front runner.